LANXESS Solutions, US, Inc. — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 June 24, 2020 Ernest Marcel, CDGP, DGSA LANXESS Solutions, US, Inc. PTSE/PSRA Group 2 Armstrong Road Shelton, CT, 06484 Reference No. 19-0077 Dear Mr. Marcel: This letter is in response to your June 10, 2019, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to mixtures containing a hazardous material that is listed in the Hazardous Materials Table (HMT) with a “+” in Column (1) and assigned Special Provision (SP) 279 in the UN Model Regulations and the International Maritime Dangerous Goods (IMDG) Code. Specifically, you ask about the classification of a product containing less than 5% toluene diisocyanate. We have paraphrased and answered your questions as follows: Q1. You seek confirmation that SP 279 in the IMDG Code and the “+” sign in Column (1) of the HMT assigns the UN Number, Proper Shipping Name, Hazard Class, and Packing Group (PG) to shipments of UN2078, but not to products containing toluene diisocyanate. A1. Your understanding is correct. Special Provision 279 and the “+” in Column (1) apply to the listed material, and do not extend to all mixtures or solutions that contain the material. It is the responsibility of the shipper to classify mixtures and solutions of toluene diisocyanate taking into account the classification criteria within the IMDG Code and the HMR. Q2. You ask whether the UN Model Regulations and the IMDG Code classify “UN2078, Toluene Diisocyanate, Class 6.1, PG II” as a toxic-by-inhalation hazard (TIH) material. A2. The answer is no. Neither the UN Model Regulations or the IMDG Code specifically identify UN2078 as a TIH material. Q3. You ask whether a hazard classification under the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS) takes precedence over the hazardous classification criteria of the various hazardous material transportation regulations (e.g., the HMR, IMDG Code, etc.).#

Page 2A3. The answer is no. For purposes of transportation within the United States, the classification criteria in the HMR take precedence over other standards, unless expressly authorized for use. For example, § 171.22 provides authorization and conditions for the use of international standards and regulations. Sincerely, Shane C. Kelley Shane Kelley Director, Standards and Rulemaking Division Office of Hazardous Material Standards#

Page 3Casey January, Ikeya CTR (PHMSA) 19-0077 From: INFOCNTR (PHMSA) Sent: Thursday, June 13, 2019 4:45 PM. To: Hazmat Interps Subject: FW: UN2078, Toluene Disocyanate, 6.1, II in Mixture(s) Attachments: Toluene Diisocyanate letter.docx; TDI DG fin -model and measured data v.xlsx; TDI DG Presentation LXS Solutions May 2018.pptx Hello Alice and Ikeya, Please see the attached documents for a letter of interpretation request. Sincerely, Lynsie, HMIC From: Marcel, Ernest [mailto:Ernest.Marcel@lanxess.com] Sent: Tuesday, June 11, 2019 2:18 PM To: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Subject: UN2078, Toluene Disocyanate, 6.1, II in Mixture(s) To whom it may concern: I would like to submit the attached letter and documents as for a formal letter of interpretation. If further information is needed, please don't hesitate to contact the undersigned. Best Regards, Head, Dangerous Goods Ernest J. Marcel, CDGP, DGSA Transportation Compliance PTSE/PSRA Group LANXESS Solutions, US, Inc. Office Phone: 203.573.2057 2 Armstrong Road, Shelton, CT 06484, USA Mobile Phone: 203.558.3408 Website: www.lanxess.us ernest.marcel@Lanxess.com "Live Safe, Work Safe"#

Page 4LANXESS Energizing Chemistry LANXESS Solution, Inc. Emest J. Marcel, CDGP, DGAC Transportation Compliance Head, Dangerous Goods LANXESS Solutions, Inc PTSE/HSEQ : Armstrong Roa Phone Office: 203.573.2057 Shelton, CT 06484 US/ Mobile: 203.558.3408 www.us.lanxess.com Email: emest.marcel@lanxess.com 10 June 2019 Pipeline & Hazardous Materials Safety Administration (PHMSA) -U.S. DOT Office of Hazardous Materials Safety, International Standard Program 1200 New Jersey Avenue S.E., E24-422, Washington D.C. 20590 E24-422 Re: UN2078, Toluene Disocyanate, 6.1, Il in Mixture(s) To Whom it my concern: Lanxess Solutions is requesting an interpretation letter on international classification of UN2078, Toluene Disocyanate, Class 6.1, Il in mixture(s). UN2078 is listed in the 172.101 with a "+ sign in Column 1 and has SP279 in the UN Recommendations and the IMDG Code. 2.0.2.9 for Classification of mixtures or solutions which states: "A mixture or solution, containing one or more substances identified by name in this Code or of this Code, is not subject to the provisions of this Code if the hazard characteristics of the mixture or classified under an N.O.S. or generic entry and one or more substances not subject to the provisions class" solution are such that they do not meet the criteria (including human experience criteria) for any Lanxess used a mathematical calculations methodology for the classification of the product. A team team determined that with less than 5% of UN2078 in the mixture that the product did not meet the consisting of two toxicologists and a chemist were assigned to develop and run the calculations. The hazardous materials classification requirements of 49CFR, the UN Recommendations or the IMDG Code. As a result of this testing Lanxess has been moving this product as non-hazardous for over ten years. told the following: Recently there have been challenges to this classification from an international source. We are being Page 1 of 2#

Page 5LANXESS . Energizing Chemistry That the SP279 means that any product with UN2078 in it must always move using the hazardous classification even if it does not meet the criteria for any hazard class. It is our understanding that SP279 only assigns the UN Number, Proper Shipping Name, the Hazard Class, and the Packing Group to UN2078. There are no further restrictions mentioned in SP279. Recommendations 2.0.2.7 or the IMDG Code 2.0.2.9 then the product would not be listed as If it is determined that the product is not hazardous per the Classification criteria in the UN UN2078. (However, it does require UN2078 to be properly listed as one of the chemicals in the mixture on the SDS form). Is our understanding of SP279 correct? 2. That UN2078 is a Toxic Inhalation Hazard (TIH) per the UN Recommendations and the IMDG Code. Checking the latest versions of both documents; neither shows UN2078 as a (TIH). Has UN2078 been updated to say that it is a TIH? 3. GHS is mentioned multiple times in regards to UN2078 being a TIH and stating that GHS over rules the various hazardous material transportation regulations. Would GHS classification criteria inhalation hazard take precedence over criteria found in Chapter 2.6 of the IMDG Code when classifying a material for transport? Issues in the work place are very different from those found in the transportation of hazardous materials. We have attached the following documents for your reference: • Latest version of the calculation method to determine the packing group for TDI in Urethane Prepolymer • TDI DG Presentation If further information is needed, please don't hesitate to contact the undersigned. I can be reach by office phone: 203.573.2057, mobile: 203.558.3408 or email at: emest.marcel@lanxess.com Thank you very much for your attention in this important subject matter Sincerely, Head, Dangerous Goods Transportation Compliance Ernest J. Marcel, CDGP, DGSA .. LANXESS Solutions, Inc. Page 2 of 2#

Page 6other. (LC50 - (48 mg/Ll There way nu sign ficant difference urmen the LC50 of mal: sustains uding tables are houser nale/femal- 66 ppm test mat = 31--141 and female rois. 3. Using the vapor method with measured data and applying a 95% confidence interval and the LC50 above -> PG III is reached at % TDI ~ 6.1 wt%. if 001 Key | Experimental result 2. For Polymer Solutions the vapor pressure of the Solute is calculated using Flory Huggins Theory (The Ideal Solution Calculation Method is not valid) 1. Using the vapor method with F-H Polymer Solutions Theory and the LC50 above →- PG Ill is reached at % TDI ~ 40 wt%. 2. Using measured vapor data and extrapolating from there using the LC50 above → PG III is also reached at % TDI ~ 40 wt%. Results and discussion Ellect levels Effectleret Bered on 95% CL isp. durstion Remarks on result 4. For the Mist /Dust method and the LC50 above →- PG Ill is achieved at %TDI < 32 wt% TDI in a Polymer Solution Mortality: Polymer Solutions containing TDI monomer are not DG if % TDI monomer is < 5wt.% 3. To be EXTRA conservative the cut-off is set to 5.0 wt% SUMMARY and CONCLUSIONS 1. The LC50 for Rat is 66 ppm (ml/m3) CONCLUSION:#

Page 7Energizing Chemistry QUALITY WORKS. LANXESS#

Page 8LANXESS • Transportation and Distribution • Stakeholder Communication • Product Stewardship • Community Outreach • Emergency Response RC and GPS are both global initiatives to improve the chemical industry's environmental, Principles health, safety, and security performance. • New Product and Process Devel Our Company Commitment • Human Health and Safety • Environmental Protection • Process Safety • Product Safety • Security#

Page 9LANXESS - Calculating Vapor Pressure and Mist Concentration of TDI in Polymer Solutions. • Concentration at which TDI in Polymer Solutions is Packing Group III • Is Solvent Methodology Applicable for TDI in Polymer Solutions? • Assessing DG Classification of TDI in Simple Solvents Outline#

Page 10REACH Dossier 66 Rat 66 LANXESS Convert to 1 hr duration: Establish LC50 in mg/Lfor TDI Reference LC50 (ppm) Duration (hours) Corr Factor to 1 hour Corrected LC50 vapor Species on LC so daya relating one on 1C so data If V ≥ IC so and LCso ≤ 3 000 ml/m'. and not meeting the criteria IF V ≥ 1/5 Lso and LCso ≤ 5000 ml/m?. and not meeting the Dangerous Goods - Criteria for Determining Packing Group Liquids having toxic r'apours shall be assigned to the following packing groups. where "V is the If V ≥ 10 LCso and ICso ≤ 1 000 ml/m': criteria for packing groups I or II. In Figure 2.6.1. the criteria according to 2.6.2.2.4.3 are expressed in graphical form. as an aid to Copyront@unted Nanot 201: All mont: deserved! The critera for inhalation toxicity of dusts and mists in 2.6.2.2.4.1 are base relating to 4 hours exposures to dusts and mists are available, such figures can be multiplied by four and the product substituted in the above criteria. i.e. LC so (4 hours) × 4 is considered the equivalent of LCso (1 hour). saturated vapour concentration in millilitres per cubic metre of air (volatility) at 20 °C and standard atmospheric for packing group I: easy classification. However, because of approximations inherent in the use of graphs. substances on or near to 1 hour exposures and where such information is available it shall be used. However. TDI LC50 (1 hr) = 66 ppm Packing group II: packing group borderlines shall be checked using numerical criteria. (a) Packing group I: (c) Packing group IT!: (b) 2.6.2.2.4.2 2.6.2.2.4.3 pressure: 2.6.2.2.4.4#

Page 11LANXESS Vapor Liquid Assume Solvent MW=174 TDI = (21(2+68) = 2.9 mole% PvapTol in Solvent = Mole% TDI x Pvap TDI TDI at 20c Project TRAX If no data available→> Use Calculation Method for Determining Packing Group 100 wt% = 100 mole% TDI Pvapor of TDI in Simple Solvent (ml/m3) PVapTo= 20.7 ppm Liquid 100% TDI Vapor at 20 °C Prapor#

Page 12LANXESS Polymer 2 molecules TDI per 1 long molecule Polymer → 21(2+1) =67 mole% TDI assume Polymer Solution is Pvap Tol in Solvent = Mole% TDI x Pvap 100% TDI at 20C Project TRAX TDI in Simple Solvent vs. TDI in Polymer Solution 2.9 mole% TDI in Solvent (2 TDI for 68 solvent molec) MW TD=174.16 Liquid#

Page 13LANXESS Polymer 5.6 wt% TDI but assume Polymer 1 moleculePolymer → 67 mole% TDI Solution is 2 molecules TDI per SIMPLE SOLUTE/SOLVENT THEORY IS NOT CORRECT FOR SOLUTE/POLYMER SYSTEMS Project TRAX PvaPTDI in Solvent = Mole% TDI x Pvap 100% TDI at 20c TDI in Simple Solvent vs. TDI in Polymer Solution 2.9 mole% TDI in Solvent (2 TDI for 68 solvent molec) MWTD=174.16 Liquid#

Page 14LANXESS PapToI = a, Pvap 100% TDI Solute - Polymer Interaction Parameter and is always positive. M Maximum value (before incompatbility = phase separation) = 0.5 Molar Volume Ratio of Polymer/Solute See Spreadsheet for Calculation Details and Parameter Values For a two component system such as we have here per Flory-Huggins, the activity of the Solute (= a1) in the Polymer = volume fraction of polymer Project TRAX gr/cm3 for range 25C to 40C The proper variable for calculating Pvap of solute (=TDI) in Polymer Solution gr/cm3 at 25C Rather... Use Flory - Huggins Polymer Solution Theory Ф. +2,Ф: is a function of VOLUME % .... not MOLE % 1.21 1.07 %: Basically ... Density of TDI Density Adiprene where#

Page 15LANXESS Volatility = (Pvap × 10º) / 101.3 PDF Volatility [=ml/m3] [= ppm] [=kPa] Not DG if Volatility TDI from TDI in Polymer Solution is < 12 ppm Pvap LCSO = 56 ppm Dangerous Goods Cut-Off Calculation and Actual Measured TDI Partial Pressure Results 100 000 PACKING GROUP I PACKINC CROUP I PACKING GROUP T 10 000 1 000 Figare 2.6.1: INHALATION TONICITY: PACKING GROIP BORDERLINES Calculated and Measured Volatility Volatility ml/s 100 NOT DANGEROL'S 12 ppm FOR TRANSPORT 10 000 1000- I.Co. mlini A = measured#

Page 16100 LANXESS V ~40% - 95% CI • Modeled + 95% Cl 10 wt% TDI in Polymer Solution ~ 6% PG HIT Not DC → Measured 15.0 14.0 13.0 12.0 110 10.0 9.0 8.0 7.0 6.0 5.0 + 4.0 + 3.0 - 20- 1.0 $ 0.0 + ml/m3 (=ppm) TDI Volatility Project TRAX Establishing the Cut-Off for TDI in Polymer Solutions 5.7 11.7 +/_ 95% Confidence Intervals of measured values 3.1 2.6 Measured and F-H Calculated Volatility Values Measured 4.1 5.6 Conclusion: Based on Measured Data for Free TDI in Polymer Solutions the DG Cut-Off Calculated F-H Theory 0.7 1.4 2.8 5.0 8.4 is set extra conservatively at 5 wt.% If wt% TDI in PrePolym = 5.3 16#

Page 17LANXESS Reference Book Chapter on Flory Huggins Polymer Solution Theory Project TRAX Notes - for additional details see the embedded Spreadsheet 1. For mists the cut-off is higher, therefore the vapor pressure method is used 2. TDI becomes PG Il when it is almost pure (=100% TDI). Detailed calculations to set the cut-off (see spreadsheet for details). Microsoft Excel Worksheet Microsoft Word 97 - 2003 Document#

Page 18Energizing Chemistry LANXESS QUALITY WORKS.#